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1.
《Mycological Research》2006,110(3):346-356
Fourteen yeast isolates belonging to the Metschnikowia clade were isolated from the digestive tracts of lacewings (Neuroptera: Chrysopidae), soldier beetles and leaf beetles (Coleoptera: Cantharidae and Chrysomelidae), and a caddisfly (Trichoptera: Hydropsychidae). The insect hosts were associated with sugary substances of plants, a typical habitat for yeasts in this clade. Based on DNA sequence comparisons and phenetic characters, the yeasts were identified as Candida picachoensis, Candida pimensis, and four undescribed taxa. Among the undescribed taxa, three yeasts were distinguished from one another and from other described taxa by nucleotide differences in the ribosomal DNA repeat, which were sufficient to consider them as new species. Two of the novel yeast species are described as Metschnikowia noctiluminum (NRRL Y-27753T) and M. corniflorae spp. nov. (NRRL Y-27750T) based in part on production of needle-shaped ascospores, which are found in most Metschnikowia species. Sexual reproduction was not observed in the third new yeast, Candida chrysomelidarum sp. nov. (NRRL Y-27749T). A fourth isolate, NRRL Y-27752, was not significantly distinct from Metschnikowia viticola and Candida kofuensis to be described as a new species. Phylogenetic analysis of the D1/D2 loop sequences placed M. noctiluminum within the M. viticola clade, while C. chrysomelidarum was a sister taxon of Candida rancensis. Metschnikowia corniflorae was phylogenetically distinct from other new species and fell outside of the large-spored Metschnikowia group.  相似文献   

2.
A total of 139 surface water samples from seven lakes and 15 rivers in southwestern Finland were analyzed during five consecutive seasons from autumn 2000 to autumn 2001 for the presence of various enteropathogens (Campylobacter spp., Giardia spp., Cryptosporidium spp., and noroviruses) and fecal indicators (thermotolerant coliforms, Escherichia coli, Clostridium perfringens, and F-RNA bacteriophages) and for physicochemical parameters (turbidity and temperature); this was the first such systematic study. Altogether, 41.0% (57 of 139) of the samples were positive for at least one of the pathogens; 17.3% were positive for Campylobacter spp. (45.8% of the positive samples contained Campylobacter jejuni, 25.0% contained Campylobacter lari, 4.2% contained Campylobacter coli, and 25.0% contained Campylobacter isolates that were not identified), 13.7% were positive for Giardia spp., 10.1% were positive for Cryptosporidium spp., and 9.4% were positive for noroviruses (23.0% of the positive samples contained genogroup I and 77.0% contained genogroup II). The samples were positive for enteropathogens significantly (P < 0.05) less frequently during the winter season than during the other sampling seasons. No significant differences in the prevalence of enteropathogens were found when rivers and lakes were compared. The presence of thermotolerant coliforms, E. coli, and C. perfringens had significant bivariate nonparametric Spearman's rank order correlation coefficients (P < 0.001) with samples that were positive for one or more of the pathogens analyzed. The absence of these indicators in a logistic regression model was found to have significant predictive value (odds ratios, 1.15 × 108, 7.57, and 2.74, respectively; P < 0.05) for a sample that was negative for the pathogens analyzed. There were no significant correlations between counts or count levels for thermotolerant coliforms or E. coli or the presence of F-RNA phages and pathogens in the samples analyzed.  相似文献   

3.
4.
Biological denitrification is a significant process in nitrogen biogeochemical cycle of terrestrial geothermal environments, and Thermus species have been shown to be crucial heterotrophic denitrifier in hydrothermal system. Five Gram-stain negative, aerobic and rod-shaped thermophilic bacterial strains were isolated from hot spring sediments in Tibet, China. Phylogenetic analysis based on 16S rRNA gene and whole genome sequences indicated that these isolates should be assigned to the genus Thermus and were most closely related to Thermus caldifontis YIM 73026T, and Thermus brockianus YS38T. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the five strains and the type strains of the genus Thermus were lower than the threshold values (95% and 70%, respectively) recommended for bacterial species, which clearly distinguished the five isolates from other species of the genus Thermus and indicated that they represent independent species. Colonies are circular, convex, non-transparent. Cell growth occurred at 37–80 °C (optimum, 60–65 °C), pH 6.0–8.0 (optimum, pH 7.0) and with 0–2.0% (w/v) NaCl (optimum, 0–0.5%). Denitrification genes (narG, nirK, nirS, and norB genes) detected in their genomes indicated their potential function in nitrogen metabolism. The obtained results combined with those of morphological, physiological, and chemotaxonomic characteristics, including the menaquinones, polar lipids, and cellular fatty acids showed that the isolates are proposed as representing five novel species of the genus Thermus, which are proposed as Thermus hydrothermalis sp. nov. SYSU G00291T, Thermus neutrinimicus sp. nov. SYSU G00388T, Thermus thalpophilus sp. nov. SYSU G00506T, Thermus albus sp. nov. SYSU G00608T, Thermus altitudinis sp. nov. SYSU G00630T.  相似文献   

5.
Habitats, phenology, food plants of adults and larvae, feeding, mating and egg-laying, the development of the larvae and pupae, and the natural enemies of Lixus paraplecticus L., L. elegantulus Boh., L. angustus Hbst., L. albomarginatus Boh., L. linnei Faust, and L. cylindrus F. were studied. Data on the geographic distribution, conservation, and economic importance of these species are given.  相似文献   

6.
A Gram-staining-negative, aerobic, non-spore-forming, non-flagellated and rod- or short rod-shaped bacterial strain, designated BH-4T, was isolated from coastal seawater in the East Sea, South Korea. Strain BH-4T grew optimally at 25 °C, at pH 7.0–7.5 and in the presence of 2 % (w/v) NaCl. Strain BH-4T exhibited the highest 16S rRNA gene sequence similarity value (96.5 %) to Hoeflea phototrophica NCIMB 14078T. It exhibited 94.2–95.5, 94.7 and 93.8 % sequence similarity values to the type strains of the other Hoeflea species, Ahrensia kielensis and Pseudahrensia aquimaris, respectively. Neighbor-joining, maximum-likelihood and maximum-parsimony phylogenetic trees revealed that strain BH-4T clustered with the type strains of A. kielensis and P. aquimaris. Strain BH-4T contained Q-10 as the predominant ubiquinone as shown in the genera Ahrensia, Pseudahrensia and Hoeflea. The fatty acid and polar lipid profiles of strain BH-4T were distinguished from those of members of the genera Ahrensia, Pseudahrensia and Hoeflea. The DNA G + C content was 49.3 mol%, lower than those of the type strains of P. aquimaris and Hoeflea species. The phylogenetic data, differential chemotaxonomic and other phenotypic properties revealed that strain BH-4T constitutes a new genus and species within the Alphaproteobacteria, for which the name Lentilitoribacter donghaensis gen. nov., sp. nov., is proposed. The type strain of Lentilitoribacter donghaensis is BH-4T (=KCTC 32082T = CCUG 62792T).  相似文献   

7.
Proleptonchoides southindiae n. gen., n. sp. (Dorylaimida: Leptonchidae), is described from soil around false tobacco (Lobelia excelsa) and cardamom (Elettaria cardamomurn) in South India. P. southindiae is prodelphic, has a short constricted esophageal bulb and flanged odontophore, and is phylogenetically close to Proleptonchus.  相似文献   

8.
Ten Bifidobacterium strains, i.e., 6T3, 64T4, 79T10, 80T4, 81T8, 82T1, 82T10, 82T18, 82T24, and 82T25, were isolated from mantled guereza (Colobus guereza), Sumatran orangutan (Pongo abeli), silvery marmoset (Mico argentatus), golden lion tamarin (Leontopithecus rosalia), pied tamarin (Saguinus bicolor), and common pheasant (Phaisanus colchinus). Cells are Gram-positive, non-motile, non-sporulating, facultative anaerobic, and fructose 6-phosphate phosphoketolase-positive. Phylogenetic analyses based on the core genome sequences revealed that isolated strains exhibit close phylogenetic relatedness with Bifidobacterium genus members belonging to the Bifidobacterium bifidum, Bifidobacterium longum, Bifidobacterium pullorum, and Bifidobacterium tissieri phylogenetic groups. Phenotypic characterization and genotyping based on the genome sequences clearly show that these strains are distinct from each of the type strains of the so far recognized Bifidobacterium species. Thus, B. phasiani sp. nov. (6T3 = LMG 32224T = DSM 112544T), B. pongonis sp. nov. (64T4 = LMG 32281T = DSM 112547T), B. saguinibicoloris sp. nov. (79T10 = LMG 32232T = DSM 112543T), B. colobi sp. nov. (80T4 = LMG 32225T = DSM 112552T), B. simiiventris sp. nov. (81T8 = LMG 32226T = DSM 112549T), B. santillanense sp. nov. (82T1 = LMG 32284T = DSM 112550T), B. miconis sp. nov. (82T10 = LMG 32282T = DSM 112551T), B. amazonense sp. nov. (82T18 = LMG 32297T = DSM 112548T), pluvialisilvae sp. nov. (82T24 = LMG 32229T = DSM 112545T), and B. miconisargentati sp. nov. (82T25 = LMG 32283T = DSM 112546T) are proposed as novel Bifidobacterium species.  相似文献   

9.
Heterotrophic growth of thraustochytrids has potential in coproducing biodiesel for transportation, as well as producing a feedstock for omega-3 long-chain (≥C20) polyunsaturated fatty acids (LC-PUFA), especially docosahexaenoic acid (DHA) for use in nutraceuticals. In this study, we compared eight new endemic Australian thraustochytrid strains from the genera Aurantiochytrium, Schizochytrium, Thraustochytrium, and Ulkenia for the synthesis of exopolysaccharide (EPS), in addition to biodiesel and LC-PUFA. Aurantiochytrium sp. strains readily utilized glucose for biomass production, and increasing glucose from 2 to 4 % w/v of the culture medium resulted in increased biomass yield by an average factor of 1.7. Ulkenia sp. strain TC 010 and Thraustochytrium sp. strain TC 033 did not utilize glucose, while Schizochytrium sp. strain TC 002 utilized less than half the glucose available by day 14, and Thraustochytrium sp. strain TC 004 utilized glucose at 4 % w/v but not 2 % w/v of the culture suggesting a threshold requirement between these values. Across all strains, increasing glucose from 2 to 4 % w/v of the culture medium resulted in increased total fatty acid methyl ester content by an average factor of 1.9. Despite an increasing literature demonstrating the capacity of thraustochytrids for DHA synthesis, the production of EPS from these organisms is not well documented. A broad range of EPS yields was observed. The maximum yield of EPS was observed for Schizochytrium sp. strain TC 002 (299 mg/L). High biomass-producing strains that also have high lipid and high EPS yield may be better candidates for commercial production of biofuels and other coproducts.  相似文献   

10.
A Gram-negative, non-motile and rod-shaped bacterial strain, designated RA2-3T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea, Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain RA2-3T was observed to grow optimally at 25 °C, at pH 7.0–7.5 and in the presence of 2 % (w/v) NaCl. Strain RA2-3T exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Litoreibacter meonggei (95.7 %), Planktotalea frisia (95.6 %), Thalassobius gelatinovorus (95.5 %) and Pelagicola litoralis (95.4 %). A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain RA2-3T clustered with the type strains of Planktotalea frisia, Pelagicola litoralis, Pacificibacter maritimus and Roseovarius marinus. Strain RA2-3T was found to contain Q-10 as the predominant ubiquinone and C18:1 ω7c as the major fatty acid. The major polar lipids detected in strain RA2-3T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain RA2-3T was 52.9 mol%. On the basis of the phylogenetic, chemotaxonomic and phenotypic properties, strain RA2-3T is considered to represent a new genus and species within the family Rhodobacteraceae, for which the name Halocynthiibacter namhaensis gen. nov., sp. nov. is proposed. The type strain of H. namhaensis is RA2-3T (=KCTC 32362T=NBRC 109999T).  相似文献   

11.
Three hundred and thirty-seven xylose-utilizing yeast strains were isolated from various natural samples. Among these, 68 strains produced xylitol in the range of 0.1–0.69 g xylitol/g xylose. Thirty-nine xylitol-producing strains were identified to be Candida tropicalis. Ten strains were found belonging to 14 known species in the genus Candida, Cyberlindnera, Meyerozyma, Pichia, Wickerhamomyces, Yamadazyma and Cryptococcus. Two strains were identified to be two Candida species and two strains (DMKU-XE142T and DMKU-XE332) were found to be a novel species. Strain DMKU-XE142T was isolated from tree bark and DMKU-XE332 was obtained from decaying plant leaf collected in Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 region of the large subunit rRNA gene (LSU) and the internal transcribed spacer (ITS) region, the two strains were determined to represent a novel Yamadazyma species although formation of ascospores was not observed. The sequences of the D1/D2 region of the LSU rRNA gene and the ITS region of the two strains were identical but differed from Yamadazyma phyllophila, the closest species in terms of pairwise sequence similarity of the D1/D2 region, by 1.7 % nucleotide substitutions and 3.5 % nucleotide substitutions in the ITS region. The name Yamadazyma ubonensis f.a., sp. nov. is proposed (type strain is DMKU-XE142T = BCC 61020T = CBS 12859T).  相似文献   

12.
A Gram-negative, non-motile and rod-shaped bacterial strain, designated BB-MW15T, was isolated from a tidal flat of the southern coast of the Korean peninsula, and its taxonomic position was investigated by using a polyphasic taxonomic approach. Strain BB-MW15T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2–3 % (w/v) NaCl. Strain BB-MW15T exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Marivita byunsanensis (96.8 %), Thalassobius maritimus (96.6 %), Sulfitobacter marinus (96.4 %) and Marinovum algicola (96.3 %). Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain BB-MW15T forms an independent lineage within the evolutionary radiation encompassed by the Roseobacter clade of the class Alphaproteobacteria. Strain BB-MW15T contained Q-10 as the predominant ubiquinone and C18:1 ω7c as the predominant fatty acid. The major polar lipids detected in strain BB-MW15T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain BB-MW15T is 62.7 mol%. Based on phylogenetic, chemotaxonomic and other phenotypic characteristics, strain BB-MW15T represents a new genus and a new species within Alphaproteobacteria, for which the name Aestuariihabitans beolgyonensis gen. nov., sp. nov. is proposed. The type strain of A. beolgyonensis is BB-MW15T (= KCTC 32324T = CCUG 63829T).  相似文献   

13.
Polyphasic analysis of ten isolates of the red-pigmented bacteria isolated from ten Arthrospira cultures originating from different parts of the world is described. The 16S rRNA analysis showed <95 % identity with the known bacteria on public databases, therefore, additional analyses of fatty acids profiles, MALDI-TOF/MS, genome sequencing of the chosen isolate and following phylogenomic analyses were performed. Gram-stain-negative, strictly aerobic rods were positive for catalase, negative for oxidase, proteolytic and urease activity. Major fatty acids were 15 : 0 iso, 17:0 iso 3 OH and 17:1 iso w9c/16:0 10-methyl. The whole phylogenomic analyses revealed that the genomic sequence of newly isolated strain DPMB0001 was most closely related to members of Cyclobacteriaceae family and clearly indicated distinctiveness of newly isolated bacteria. The average nucleotide identity and in silico DNA–DNA hybridisation values were calculated between representative of the novel strains DPMB0001 and its phylogenetically closest species, Indibacter alkaliphilus CCUG57479 (LW1)T (ANI 69.2 % is DDH 17.2 %) and Mariniradius saccharolyticus AK6T (ANI 80.02 % isDDH 26.1 %), and were significantly below the established cut-off <94 % (ANI) and <70 % (isDDH) for species and genus delineation.The obtained results showed that the analysed isolates represent novel genus and species, for which names Arthrospiribacter gen nov. and Arthrospiribacter ruber sp. nov. (type strain DPMB0001 = LMG 31078 = PCM 3008) is proposed.  相似文献   

14.
15.
Bacteria of the genus Massilia often colonize extreme ecosystems, however, a detailed study of the massilias from the Antarctic environment has not yet been performed. Here, sixty-four Gram-stain-negative, aerobic, motile rods isolated from different environmental samples on James Ross Island (Antarctica) were subjected to a polyphasic taxonomic study. The psychrophilic isolates exhibited slowly growing, moderately slimy colonies revealing bold pink-red pigmentation on R2A agar. The set of strains exhibited the highest 16S rRNA gene sequence similarities (99.5–99.9%) to Massilia violaceinigra B2T and Massilia atriviolacea SODT and formed several phylogenetic groups based on the analysis of gyrB and lepA genes. Phenotypic characteristics allowed four of them to be distinguished from each other and from their closest relatives. Compared to the nearest phylogenetic neighbours the set of six genome-sequenced representatives exhibited considerable phylogenetic distance at the whole-genome level. Bioinformatic analysis of the genomic sequences revealed a high number of putative genes involved in oxidative stress response, heavy-metal resistance, bacteriocin production, the presence of putative genes involved in nitrogen metabolism and auxin biosynthesis. The identification of putative genes encoding aromatic dioxygenases suggests the biotechnology potential of the strains. Based on these results four novel species and one genomospecies of the genus Massilia are described and named Massilia rubra sp. nov. (P3094T = CCM 8692T = LMG 31213T), Massilia aquatica sp. nov. (P3165T = CCM 8693T = LMG 31211T), Massilia mucilaginosa sp. nov. (P5902T = CCM 8733T = LMG 31210T), and Massilia frigida sp. nov. (P5534T = CCM 8695T = LMG 31212T).  相似文献   

16.
Isolations from oak symptomatic of Acute Oak Decline, alder and walnut log tissue, and buprestid beetles in 2009–2012 yielded 32 Gram-negative bacterial strains showing highest gyrB sequence similarity to Rahnella aquatilis and Ewingella americana. Multilocus sequence analysis (using partial gyrB, rpoB, infB and atpD gene sequences) delineated the strains into six MLSA groups. Two MLSA groups contained reference strains of Rahnella genomospecies 2 and 3, three groups clustered within the Rahnella clade with no known type or reference strains and the last group contained the type strain of E. americana. DNA–DNA relatedness assays using both the microplate and fluorometric methods, confirmed that each of the five Rahnella MLSA groups formed separate taxa. Rahnella genomospecies 2 and 3 were previously not formally described due to a lack of distinguishing phenotypic characteristics. In the present study, all five Rahnella MLSA groups were phenotypically differentiated from each other and from R. aquatilis. Therefore we propose to classify the strains from symptomatic oak, alder and walnut and buprestid beetles as: Rahnella victoriana sp. nov. (type strain FRB 225T = LMG 27717T = DSM 27397T), Rahnella variigena sp. nov. (previously Rahnella genomosp. 2, type strain CIP 105588T = LMG 27711T), Rahnella inusitata sp. nov. (previously Rahnella genomosp. 3, type strain DSM 30078T = LMG 2640T), Rahnella bruchi sp. nov. (type strain FRB 226T = LMG 27718T = DSM 27398T) and Rahnella woolbedingensis sp. nov. (type strain FRB 227T = LMG 27719T = DSM 27399T).  相似文献   

17.
18.
Two gram-negative, catalase- and oxidase-positive, bacillus-shaped bacterial strains were isolated from the semen of two rams. 16S rRNA gene sequencing demonstrated that both isolates represented a distinct subline within the family Pasteurellaceae with <95% sequence similarity to any recognized member of this family. Sequencing of rpoB and infB genes confirmed this finding with the semen isolates representing a new sub-line within the family Pasteurellaceae. The main cell fatty acids of strain DICM-00342T were C14:0, C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c/iso-C15:0 2OH). Ubiquinone Q-8 was the major quinone and 1,3-diaminopropane was the predominat polyamine. Major polar lipids were phosphatidylglycerol and phosphatidylethanolamine. The new genus can be phenotypically distinguished from currently described genera of this family based on physiological traits and a combination of signature amino acids in the RpoB protein sequence. On the basis of these results we describe a new genus and species for which we propose the name of Seminibacterium arietis gen. nov., sp. nov. (DICM11-00342T = CCUG 61707T = CECT 8033T).  相似文献   

19.
A novel endophytic actinomycete, designated strain NEAU-J3T, was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain NEAU-J3T fell within the family Micromonosporaceae. The strain was observed to form an extensively branched substrate mycelium, which carried non-motile oval spores with a smooth surface. The cell walls of strain NEAU-J3T were determined to contain meso-diaminopimelic acid and galactose, ribose and glucose were detected as whole-cell sugars. The major menaquinones were determined to be MK-9(H4) and MK-9(H6). The phospholipids detected were phosphatidylcholine and phosphatidylethanolamine. The major cellular fatty acids were determined to be C16:0, C18:1 ω9c, C18:0, C17:0, C17:1 ω7c, anteiso-C17:0, C16:1 ω7c and C15:0. The DNA G + C content was 62.5 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J3T is considered to represent a novel species of a new genus within the family Micromonosporaceae, for which the name Wangella harbinensis gen. nov., sp. nov. is proposed. The type strain of Wangella harbinensis is strain NEAU-J3T (=CGMCC 4.7039T = DSM 45747T).  相似文献   

20.
We used selective agar media for culturing bacteria from the caecum of mice fed a high calorie diet. In addition to the isolation of Enterobacteriaceae growing on a medium containing cholesterol and bile salts, we focused on the characterization of strain CT-m2T, which, based on 16S rDNA analysis, did not appear to correspond to any currently described organisms. The isolate belongs to the Clostridium cluster XIV and is most closely related to members of the Lachnospiraceae, including the genera Anaerostipes, Blautia, Butyrivibrio, Clostridium, Coprococcus, Eubacterium, Robinsoniella, Roseburia, Ruminococcus and Syntrophococcus (≤90?% similarity). Strain CT-m2T is a non-motile Gram-positive rod that does not form spores and has a G?+?C content of DNA of 48.5?%. Cells grow under strictly anoxic conditions (100?% N2) and produce acetate and butyrate after growth in reduced WCA broth. In contrast to related species, the new bacterium does not metabolize glucose and is positive for phenylalanine arylamidase, and its major cellular fatty acid is C14:0. Based on phylogenetic and phenotypic studies, the isolate merits recognition as a member of a novel genus and species, for which the name Acetatifactor muris is proposed. The type strain is CT-m2T (=?DSM 23669T?=?ATCC BAA-2170T).  相似文献   

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